Use testuser to clone apertis-test-cases

With new git version additional checks are done to confirm if a repository is safe. One of such checks is the ownership of the files, which triggers an error by default. Since QA Report App runs some tests with testuser this check does no pass causing the pipeline to fail.

Workaround this issue by cloning the repository with the testuser.

Signed-off-by: Walter Lozano walter.lozano@collabora.com